I've never used one. Reduces recoil? Probably not. I'm not an armorer so I may need some help on this - the return spring is just that - it controls the amount of pressure needed to move the slide back to eject the used round and reload a new round.

I've not fired anything (auto) with a ported barrel. In all the many I've tried, the only one I would've considered it to be best suited to would've been a Dessert Eagle. Everything else I've fired has been managable with a proper grip. In what I own I don't see a need for having a ported barrel. Your needs/wants may differ.